The primary goal is to develop general methodology and tools for geometric validation studies described in Projects 2-4. We also aim to develop transportable versions of these resources to facilitate benchmarking and inter-comparison in the collective research community investigating methods for segmentation of medical images. Our specific aims are to: (1) Develop and implement a suite of geometric and statistical measures to characterize accuracy and reproducibility of segmentation methods that find surfaces; (2) Develop a method for producing large numbers of realistic test images with the time segmentations attached; and (3) Develop transportable validation tools and image data for community use.